Vacuum assisted treatment of the skin has recently been described in several patent applications, including: U.S. patent application Ser. No. 11/498,456; U.S. patent application Ser. No. 11/401,674; EP Patent Application No. 050007952.4; U.S. patent application Ser. No. 11/057,542; U.S. patent application Ser. No. 10/498,382; and PCT/IL02/00635, the disclosures of which are herein incorporated by reference in their entirety. Clinical applications of vacuum assisted treatments of the skin include, among others, light based aesthetic treatments of the skin such as hair removal, treatment of pigmented lesions, and treatment of vascular lesions as well as medical treatments such as painless injections. An evacuation chamber, which is currently utilized for pain reduction as well as to increase efficacy and safety of light based aesthetic treatments, can use a micro-switch to enable the generation of vacuum in the evacuation chamber. When the operator places the chamber contacts the skin on the treatment site, the switch is depressed and the air is removed from the vacuum chamber. This can be achieved by slightly pressing the skin while placing the evacuation chamber over the treatment site, resulting in the activation of the micro-switch and the activation of the vacuum.
Although generally satisfactory, a disadvantage of the utilization of a micro-switch on the skin can result if the skin lacks stiffness or rigidity. While pressing the skin for the activation of the micro-switch, the skin can recede. The receding degree depends on the specific patient. Skin receding is particularly significant in obese patients or in soft areas such as the axilla or bikini line or the chin. As a result, the micro-switch may not be activated, and evacuation over the skin may not occur. Consequently, a treatment may be more difficult, or in certain circumstances, may not be feasible.